System and method for cleaning a log structure

A method for cleaning one or more log structures in a disk array, the disk array including one or more log-enabled logical units, each log-enabled logical unit including one or more segments, each segment including live data, the method for each log-enabled logical unit comprising:

• ordering the one or more segments into a hot list according to age, with the youngest segment at the beginning of the hot list and the oldest segment at the end of the hot list, the youngest segment being the most recently used segment and the oldest segment being the least recently used segment;
• pushing one or more of the oldest segments in the hot list to a cleaning matrix, the cleaning matrix grouping segments according to age and percent of live data in the segment;
• traversing the cleaning matrix looking for a segment;
• determining whether enough live data has been found to write a complete segment;
• sequentially repeating the previous two processes until enough live data has been found to write a complete segment;
• reading data from the one or more found segments;
• and
• writing the read live data into an unused segment.

A system for cleaning a log structure, the log structure including one or more segments, each segment including live data, the system comprising:

• means for ordering the one or more segments into a hot list according to age, with the youngest segment at the beginning of the hot list and the oldest segment at the end of the hot list, the youngest segment being the most recently used segment and the oldest segment being the least recently used segment;
• means for pushing one or more of the oldest segments in the hot list to a cleaning matrix, the cleaning matrix grouping segments according to age and percent of live data in the segment;
• means for traversing the cleaning matrix looking for a segment;
• means for determining whether enough live data has been found to write a complete segment;
• means for sequentially repeating the previous two processes until enough live data has been found to write a complete segment;
• means for reading data from the one or more found segments;
• and
• means for writing the read live data into an unused segment.

A system for cleaning one or more log structures in a disk array, the disk array including one or more log-enabled logical units, each log-enabled logical unit including one or more segments, each segment including live data, the system for each log-enabled logical unit comprising:

• means for ordering the one or more segments into a hot list according to age, with the youngest segment at the beginning of the hot list and the oldest segment at the end of the hot list, the youngest segment being the most recently used segment and the oldest segment being the least recently used segment;
• means for pushing one or more of the oldest segments in the hot list to a cleaning matrix, the cleaning matrix grouping segments according to age and percent of live data in the segment;
• means for traversing the cleaning matrix looking for a segment;
• means for determining whether enough live data has been found to write a complete segment;
• means for sequentially repeating the previous two processes until enough live data has been found to write a complete segment;
• means for reading data from the one or more found segments;
• and
• means for writing the read live data into an unused segment.

A computer program product for cleaning a log structure, the log structure including one or more segments, each segment including live data, the computer program product comprising computer useable medium, the computer useable medium having computer readable program code thereon, the computer readable program code comprising:

• program code for ordering the one or more segments into a hot list according to age, with the youngest segment at the beginning of the hot list and the oldest segment at the end of the hot list, the youngest segment being the most recently used segment and the oldest segment being the least recently used segment;
• program code for pushing one or more of the oldest segments in the hot list to a cleaning matrix, the cleaning matrix grouping segments according to age and percent of live data in the segment;
• program code for traversing the cleaning matrix looking for a segment;
• program code for determining whether enough live data has been found to write a complete segment;
• program code for sequentially repeating the previous two processes until enough live data has been found to write a complete segment;
• program code for reading data from the one or more found segments;
• and
• program code for writing the read live data into an unused segment.

A computer program product for cleaning one or more log structures in a disk array, the disk array including one or more log-enabled logical units each log-enabled logical unit including one or more segments, each segment including live data, the computer program product comprising computer useable medium, the computer useable medium having computer readable program code thereon, the computer readable program code comprising:

• program code for ordering the one or more segments into a hot list according to age, with the youngest segment at the beginning of the hot list and the oldest segment at the end of the hot list, the youngest segment being the most recently used segment and the oldest segment being the least recently used segment;
• program code for pushing one or more of the oldest segments in the hot list to a cleaning matrix, the cleaning matrix grouping segments according to age and percent of live data in the segment;
• program code for traversing the cleaning matrix looking for a segment;
• program code for determining whether enough live data has been found to write a complete segment;
• program code for sequentially repeating the previous two processes until enough live data has been found to write a complete segment;
• program code for reading data from the one or more found segments;
• and
• program code for writing the read live data into an unused segment.